Vodacom poor customer service

Good day at, I have been receiving statements from Vodacom for an overdue amount of R3500, however my account has always been up to date. I have requested a statement of the outstanding amount, but none has been provided. I called the Vodacom call centre, and they could not pick up this letter or the amount. They gave me an amount of R180 or so and confirmed there was no other amount. Yet I am still receiving these letters. The account has also been transferred from personal to business. When I call customer service they say it is a business account and cannot help me, when I call Vodacom business, they say it is a personal account and cannot help me. Vodacom are totally in a mess.